There are many different types of robots, but each uses the same fundamental elements. The four basic parts of every robot are the mechanics, electronics, and programming. Builders should determine the purpose of a robotic project, and combine components from these four categories in order to complete the assembly.
Beginning builders do not typically need complex kits or large amounts of money to make a robot, as a simple autonomous robotic project can be completed inexpensively. New hobbyists should choose a goal for the robot that is not overly ambitious or advanced. Many simple robots are designed to move around a room and avoid objects, while others are programmed to seek sunlight and avoid darkness. A simple purpose allows hobbyists to stay focused on one overall goal for the robotic project.
The mechanics of a robot should be built with a specific overall goal in mind. A robotic frame is necessary and should be large and sturdy enough to support the critical components of the robot, but also as lightweight as possible. Wheels should be selected based on the intended surface. A robot that will be used outdoors should have large wheels with treads, while wheels for indoor robots can typically be smaller and lighter.
Builders should also choose a wheel system that is simple to control. A robot with only two wheels, for instance, is much easier to build and control than a project with four wheels. Two-wheeled robots do not require steering mechanisms, but can be controlled by stopping or reversing one of the wheels. Simple is often better for new robotic designs.
The necessary array of electronic parts can seem intimidating and complicated for hobbyists working to make a robot. As with the hardware, however, robot electronics do not need to be overly complex, and simplicity is often an advantage. The minimum electronic components required for a robotic project include motors, batteries, sensors, and a micro-controller.
Motors for robots are almost always the direct current (DC) type. These should be linked directly to the wheels, or connected to drive shafts using gears. Robots with two wheels often also have two motors, with one motor placed on each side of the frame. Engaging both motors drives the robot forward, while stopping either the left or right motor causes the robot to turn in that direction.
Batteries are typically used to supply power to the electronic components. Builders who make a robot should select batteries that are lightweight, yet still provide ample power. Rechargeable batteries are often recommended. Common alkaline batteries, such as those found in flashlights, are often too heavy and expensive to constantly replace.
Most robots require a micro-controller. This device is a simple computer that acts as the brain of a robot. Micro-controllers contain programming, or a set of instructions. Most micro-controller programming can be easily updated using a computer.
Sensors are usually required to allow a robot's interaction with the environment. They are typically linked directly to the micro-controller. Builders who make a robot should select sensors that meet the specific goals of the project. A sunlight seeking robot, for instance, may need a photosensor to detect light levels. More complex robotic projects often use ultrasonic and infrared sensors to determine distances between objects, and avoid colliding with obstacles.